1. Field of the Invention
The present invention relates, in general, to refrigerators and, more particularly, to the bottom structure for refrigerators.
2. Description of the Prior Art
Referring to FIG. 1, the structure for conventional refrigerators is described hereafter. As shown in the drawing, the structure includes an exterior casing 2 and an interior casing 4. The exterior casing 2 consists of a top plate and two side plates, is made of metal plates and defines the exterior of the refrigerator. The interior casing 4 is disposed in the exterior casing 2, is made of a synthetic resin plate and defines a freezer compartment and a refrigerator compartment.
The gap between the exterior and interior casings 2 and 4 is filled with insulating urethane foaming liquid, thereby forming a foam layer. In order to form the foam layer, after the interior casing 4 is positioned in the exterior casing 2, a front center panel 7 is provided at the front of the exterior casing 2, a bottom plate 8 is provided at the bottom of the exterior casing 2 and a back plate 6 is provided at the rear of the exterior casing 2. Thereby, the gap between the exterior and interior casings 2 and 4, through which the insulating urethane foaming liquid is able to leak, is blocked.
Incidentally, a compressor base plate 10 is positioned under the rear part of the bottom plate 8 so as to define a machine compartment and support a compressor (not shown) mounted in the machine compartment.
In brief, according to the conventional structure of the refrigerator, the lower structure of the refrigerator consists of the bottom plate 8 and the compressor base plate 10.
In the conventional structure of the refrigerator, the exterior casing 2, the bottom plate 8 and the compressor base plate 10 are made of metal plates. When the conventional structure is made of the metal plates, the connection strength between the parts of the structure is lacking, thus being easily damaged by the external impact. In particular, when an external impact is applied to the structure as may occur in the case where the refrigerator is transported or the refrigerator is set down on the floor, the connecting portion between the external casing 2 and the bottom plate 8 may be broken or deformed, thus showing a defect in strength. Such a defect is also found in the connecting portion between the exterior casing 2 and the compression base plate 10.
Further, since the lower portion of the refrigerator is made of metal, the total weight of the refrigerator is not only heavy, but the manufacturing cost of the refrigerator is high.
Additionally, the assembly of the refrigerator is difficult because screws are required to assemble together the metal plates, such as the external casing 2 and the bottom plate 8.
Besides, after the external plate 2 is connected with the bottom plate 8, it is needed to seal the gap between the external portion 2 and the bottom plate 8. When the gap between the external portion 2 and the bottom plate 8 is filled with a foaming liquid so as to seal the connecting portion, the foaming liquid may leak out through the gap, thus causing a defect in the product.
Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and an object of the present invention is to provide a lower structure of a refrigerator having improved impact resistance.
Another object of the present invention is to provide a lower structure of a refrigerator, allowing its parts to be simplified, thereby reducing manufacturing cost and improving assembly efficiency.
In order to accomplish the above object, the present invention provides a bottom structure for refrigerators, comprising the base plate made of synthetic resin utilizing an injection molding process and having a cavity filled with foam, a machine compartment casing engaging with the top surface of the base plate and defining a machine compartment of a refrigerator and fitting means for engaging the lower edge of an exterior plate with the top surface of the base plate.
In another embodiment, the base plate may have a plurality of fitting slits on its top surface, while the machine compartment casing may have a plurality of fitting projections at positions corresponding to the fitting slits.
In a further embodiment, the fitting means may comprise a fitting groove formed on the top surface of the base plate and a fitting rail formed on the lower edge of the external plate.
In yet another embodiment, the base plate may be partially made of metal at a machine-seating portion.
In a still further embodiment, the machine compartment casing may be formed of synthetic resin.
In an additional embodiment, the base plate may be formed with a foaming liquid inlet on its top surface, the foaming liquid inlet communicating with the cavity of the base plate and a gap between the exterior and interior casings.
In another embodiment, the corners or the edges of the machine compartment casing may be rounded off.